Contact Terry Shuchat @ http://www.kspphoto.com/. He is quite a collector and has one or two vintage aircraft cameras on display and might be able to point you to a good source of info. _________________
While a picture may be worth a thousand words, a quality photograph is worth a million.

If you find a source for military manuals for cameras, please let me know. I just bought a 1942 K-20 aerial camera in its original case. Manual was missing. Sounds like your camera is bigger than mine (4 x 5). Good luck.